What is provided is a tree harvesting apparatus and, more specifically, a tree harvesting apparatus for severing and accumulating severed trees.
In the harvesting of trees, it is typical to mount a tree harvesting apparatus to the boom of a carrier vehicle such as a feller buncher or crawler tractor. The harvesting apparatus referred to herein is typically referred to as a harvesting or cutting head which typically employs a circular cutting saw to sever the tree, a means to grip and hold the tree while and after the tree is severed, and a base member which partially overlays the circular saw for supporting the tree off of the circular saw as the tree is being cut. Those cutting heads which accumulate the trees on the head itself oftentimes employ a tree accumulation plate or member for supporting the severed trees. In recent years, machine productivity has been become a major issue since the end users of such machines are increasingly under pressure to make a return on their investments in the forestry industry. To this end, it has been found to be desirable to provide the cutting heads with the ability to transport a greater number of trees.
In order to accomplish the aforementioned objective, however, it is necessary to overcome certain design restrictions in the design of the cutting head itself. For instance, increasing the tree accumulation area by increasing the diameter of the circular saw results in a much larger cutting head than that which is actually needed to cut through the largest desired tree. Furthermore, extending the tree accumulation area out over the teeth of the cutting saw requires sufficient clearance between the accumulation member and teeth to prevent contact between the two when the tree accumulation area is subject to the weight of the trees. In addition, for those arrangements in which the base member and accumulation member comprise a unitary structure, elevating the accumulation member as described above causes the base member to be further elevated above the cutting plane of the circular saw which may impede the cutting of the tree by causing the tree to wedge onto the base member.
There currently exist numerous prior art attempts to increase the area available to store severed trees. For example, U.S. patent application Ser. No. 5,794,674 which issued to Kurelek on Aug. 18, 1998, teaches a felling and accumulating head which utilizes an accumulation area which is elevated in respect to a base plate and connected therewith by a ramp. Although the aforementioned arrangement may be adequate for its respective intended purpose, it still requires the need for three separate parts (e.g., base plate, ramp and accumulation area) which may add to the complexity and cost of the design. Also, U.S. Pat. No. 4,446,897, which issued to Kurelek on May. 8, 1984, teaches a felling head in which the accumulation member only extends to the teeth of the circular saw. Although this design may also be adequate for its intended purpose, the inability of the accumulation member to extend past the teeth of the circular saw limits its tree storage capacity.
The present invention is directed to overcoming one or more of the problems as set forth above.
In an embodiment of the present invention, a harvesting apparatus is provided. The harvesting apparatus comprises a frame member, a cutting device mounted to the frame member, and at least one cutting member attached to the cutting device. A base member partially overlays the cutting device, and a tree accumulation member is positioned adjacent the base member and is coplanar therewith and extends over at least a portion of the cutting member.
In another embodiment of the present invention, a harvesting apparatus is provided. The harvesting apparatus comprises a frame member, a cutting device mounted to the frame member and having a central portion and a rim portion. A support plate partially overlays the cutting device and is separated from the cutting device by a separation distance increasing from a location adjacent the central portion to the outer rim portion.
In yet another embodiment of the present invention, a cutting device is provided. The cutting device comprises a central portion and an outer rim portion. A cutting tooth is attached to the outer rim portion and defines an upper and lower cutting plane. The cutting device further comprises a web portion, having a web portion upper surface, separated from the upper cutting plane adjacent the central portion by a first distance, and separated from the upper cutting plane adjacent the outer rim portion by a second distance wherein the second distance is greater than the first distance.